JPH0728076B2 - Laser power control device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a control device for keeping the power of a laser beam intermittently output from a laser generator constant.

[Conventional technology]

Conventionally, as this type of device, there is known one in which the output of a detector attached to a laser emitting portion and the output of a power converter connected to the detector are visually observed for a certain period of time, and the power of a laser generator is manually adjusted based on the result. There is.

[Problems to be Solved by the Invention]

As described above, the manual adjustment requires complicated work and is time-consuming, so that the adjustment is usually performed only about once a day. For this reason, there is a problem in that it is impossible to cope with the reduction in power due to deterioration (wear) of the laser generating lamp or contamination of the emission lens due to smoke or the like.

Therefore, an object of the present invention is to provide a control device capable of controlling laser power with high accuracy.

[Means for Solving the Problems]

A detector that detects the power of the laser beam intermittently output from the laser generator, a converter that converts the output signal into a predetermined voltage signal, and whether the laser irradiation is being performed based on the output signal of the converter. A laser irradiation presence / absence detector for detection, a signal holding circuit for holding the output signal from the converter based on the output signal, and an adjusting operation for adjusting the output of the signal holding circuit to a predetermined set value. And
The laser power from the laser generator is controlled to be substantially constant based on the output of the regulator.

[Action]

Automation is easy by detecting the laser power and performing feedback control. However, in the case where the laser beam is intermittently output, there is a possibility that the detection may be performed when the laser is not irradiated, and automation cannot be performed up to this point. Therefore, a laser irradiation presence / absence detector and a signal holding circuit are provided so that the laser power can be correctly detected and automation can be realized.

〔Example〕

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a time chart for explaining its operation. First
In the figure, 1 is a work (product) to be processed by a laser beam, 2 is a laser power detector, 3 is a laser emitting section, 4 is a laser generator, 5 is a laser power converter, 6 is a laser power controller, and 7 is a laser power controller. Is a signal (data) holding circuit, 8
Is a laser irradiation presence / absence detector.

The operation will be described below with reference to these figures.

When the laser generator 4 receives the laser irradiation command as shown in FIG. 2A, the laser generator 4 irradiates the work 1 with the laser beam through the laser emission unit 3. The power of this laser beam is detected by the detector 2 and further the laser power converter 5 including an amplifier and the like.
Is converted into a voltage signal of a predetermined level. The output is
For example, it is shown as shown in FIG. A certain threshold P ₀ (see FIG. 2B) is set in the laser irradiation presence / absence detector 8, and when the output signal from the laser power converter 5 exceeds the threshold P ₀ , the laser is emitted. It is detected that irradiation is in progress, and the data holding circuit 7 is instructed to update the data after a certain time T ₁ . Since the data holding circuit 7 has at least a memory function and holds the previous data until the next data update instruction, even if the laser irradiation is intermittently performed, there is a possibility that erroneous control is performed based on erroneous detection. It can be lost. Examples of output waveforms of the laser irradiation presence / absence detector 8 and the data holding circuit 7 are shown in FIGS. 2C and 2D, respectively. The output of the data holding circuit 7 is compared and calculated with a predetermined set value by the laser power controller 6, and the laser power is always kept constant by operating, for example, the current of the laser generator 4 based on the output. To

〔The invention's effect〕

According to the present invention, the power calibration work once a day is completely automated manually as in the conventional case. Therefore, not only the labor saving but also the reduction of the laser power of about 2 to 3% per day is automatically performed. It is possible to provide a stable and highly reliable laser generator capable of compensation.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a time chart for explaining its operation. Explanation of symbols 1 ... Workpiece, 2 ... Laser power detector, 3 ... Laser emitting section, 4 ... Laser generating section, 5 ... Laser power converter, 6 ... Laser power controller, 7 ... Data Holding circuit, 8 ... Laser irradiation presence / absence detector.

Claims (1)

[Claims] 1. A detector for detecting the power of a laser beam intermittently output from a laser generator, a converter for converting the output signal into a predetermined voltage signal, and laser irradiation from the output signal of the converter. A laser irradiation presence / absence detector for detecting whether or not it is inside, a signal holding circuit for holding the output signal from the converter based on the output signal, and an adjustment of the output of the signal holding circuit so as to match a predetermined set value. A laser power control device comprising: an adjuster for performing calculation, and controlling the laser power from the laser generator to be substantially constant based on the output of the adjuster.